package com.itheima.reggie.controller;

import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.util.UUID;


/**
 * 文件上传和下载
 */
@RestController
@RequestMapping("/common")
@Slf4j
public class CommonController {
    @Value("${reggie.path}")
    private String basePath;

    //上传
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
        log.info(file.toString());
        //原始文件名
        String originalFilename = file.getOriginalFilename();
        String substring = originalFilename.substring(originalFilename.lastIndexOf("."));

        //使用UUID生成新的文件名,防止文件名重复造成文件覆盖
        String fileName = UUID.randomUUID().toString() + substring;

        //创建一个目标对象
        File dir = new File(basePath);
        //判断当前对象是否存在
        if (! dir.exists()){
            //目标不存在,创建
            dir.mkdirs();
        }

        //将文件存到指定位置
        try {
            file.transferTo(new File(basePath+fileName));

        } catch (IOException e) {
            e.printStackTrace();
        }
        return R.success(fileName);

    }


    //下载
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        try {
            //输入流,读取文件内容
            FileInputStream fileInputStream = new FileInputStream(new File(basePath+name));

            //输入流,写会浏览器
            ServletOutputStream outputStream = response.getOutputStream();

            response.setContentType("image/jpeg");

            int len = 0;
            byte[] bytes = new byte[1024];
            while ((len = fileInputStream.read(bytes)) != -1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }

            //关闭资源
            outputStream.close();
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }


    }
}
